$1)n_{KOH}=1,5 mol\Rightarrow n_{SO_2}+n_{CO_2}=1,5 mol\Rightarrow \overline{M}_{muối}=\frac{174}{1,5}=116 $$\Rightarrow \frac{116-80}{2}<M<\frac{116-60}{2}\Rightarrow 18<M<28\Rightarrow M:Na$
$2)$
$2M+2nHCl\rightarrow 2MCl_n+nH_2\uparrow$
$x 0,5nx$
$\Rightarrow \begin{cases}x=\frac{1,2}{M} \\0,5nx=\frac{1,2+200-201,1}{2} \end{cases}\Rightarrow M=12n\Rightarrow \begin{cases}n=2 \\M=24 \end{cases}\Rightarrow M:Mg$